NAME¶

AtteanX::Store::DBI - Database quad-store

VERSION¶

This document describes AtteanX::Store::DBI version 0.002

SYNOPSIS¶

 use Attean;
 my $store = Attean->get_store('DBI')->new( dbh => $dbh );

DESCRIPTION¶

AtteanX::Store::DBI provides a quad-store backed by a relational database.

ATTRIBUTES¶

"dbh"

ROLES¶

This class consumes Attean::API::QuadStore, Attean::API::MutableQuadStore, and Attean::API::BulkUpdatableStore.

METHODS¶

"new ( dbh => $dbh )"

Returns a new quad-store object backed by the database referenced by the supplied database handle.

"init()"

Create the tables and indexes required for using the database as a quadstore.

"temporary_store()"

Returns a temporary (in-memory, SQLite) store.

"get_quads ( $subject, $predicate, $object, $graph )"

Returns a stream object of all statements matching the specified subject, predicate and objects. Any of the arguments may be undef to match any value, or an ARRAY reference of terms that are allowable in the respective quad position.

"count_quads ( $subject, $predicate, $object, $graph )"

Returns the count of all statements matching the specified subject, predicate and objects. Any of the arguments may be undef to match any value, or an ARRAY reference of terms that are allowable in the respective quad position.

"get_graphs"

Returns an iterator over the Attean::API::Term objects comprising the set of graphs of the stored quads.

"add_quad ( $quad )"

Adds the specified $quad to the underlying model.

"remove_quad ( $statement )"

Removes the specified $statement from the underlying model.

"create_graph( $graph )"

This is a no-op function for the memory quad-store.

"drop_graph( $graph )"

Removes all quads with the given $graph.

"clear_graph( $graph )"

Removes all quads with the given $graph.

"begin_transaction"

Begin a database transaction.

"abort_transaction"

Rollback the current database transaction.

"end_transaction"

Commit the current database transaction.

"begin_bulk_updates"

Begin a database transaction.

"end_bulk_updates"

Commit the current database transaction.

"database_type"

Returns the database type name as a string (e.g. 'mysql', 'sqlite', or 'postgresql').

"initialize_version"

Insert data into the attean_version table.

"create_schema_file"

Returns the path to the file containing the database DDL for quadstore creation for the current database type if available, undef otherwise.

"drop_schema_file"

Returns the path to the file containing the database DDL for quadstore deletion for the current database type if available, undef otherwise.

"available_database_types"

Returns the names of the database types for which the system has schemas available to create and drop quadstore tables.

"dbi_connect_args ( $type, %args )"

"dbi_connect_args ( %args )"

Returns a quad "$dsn, $user, $password, \%connect_args" suitable for passing to "DBI->connect" to obtain a database handle to be used in constructing a "AtteanX::Store::DBI" quadstore.

%args must contain a value for the "database" key. It may also contain values for the optional keys: "user", "password", "host", and "port".

If invoked as a class method, the $type parameter is required, and must be one of the database types returned by "available_database_types".

If invoked as an object method, the $type parameter must not be included; this information will be obtained directly from the "AtteanX::Store::DBI" object.

"plans_for_algebra( $algebra, $model, $active_graphs, $default_graphs )"

For BGP algebras, returns a DBI-specific Attean::API::Plan object, otherwise returns undef.

"cost_for_plan( $plan )"

Returns the estimated cost for a DBI-specific query plan, undef otherwise.

BUGS¶

Please report any bugs or feature requests to through the GitHub web interface at <https://github.com/kasei/perlrdf2/issues>.

AUTHOR¶

Gregory Todd Williams "<gwilliams@cpan.org>"

COPYRIGHT¶

Copyright (c) 2014--2020 Gregory Todd Williams. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.